Bought an 05 Cobalt a couple weeks ago and have been plagued by the "security immobilizer" issue. Had the same issue on an old Oldsmobile from '04. Knock on wood I haven't had an issue on our '07 HHR yet.
To get to the point I bought a Xpresskit PLJX bypass to hook up, and will later hookup a remote start. Everything seemed great until I unplug the harness from the ignition switch and found I have red/white, yellow, brown, white, white/black instead of the orange, blue, brown, white, white/black wires on the bypass instructions.
Figured if I took the silly security from the key out of the equation I should be able to start my car without worrying I'll have to play the 10 minute security reset game.
If anyone has install a bypass on one of these and can help I'd be much appreciative. I only have to locate the White and Blue wire according to these instrutions, but as mentioned above I don't have a Blue wire on the ignition switch
The white wire breaks to pass through the PLJX and I just have to tie into the blue wire and ground it.
Thanks in advance, looks like a lot of useful information on this site. So far I've replaced the headlights, front speakers, interior door handles, original battery and an O2 sensor in the few weeks I've owned this. Cosmetically the car now looks new. Once I get this security fiasco straight I think I'm going to enjoy this car for years to come. If I don't I'm going to continue to hate how undependable it has been.